TABLE 16.
Different resistance mechanisms among Enterobacterales and P. aeruginosa against four approved new BLBLIsa
| Drugb | Resistance mechanisms |
|---|---|
| CAZ-AVI | Class B MBLs |
| Hyperexpression of efflux pumps | |
| Porin alterations | |
| Increased expression of the blaKPC gene or mutations on Ω-loop of KPC enzymes | |
| Mutations in PBPs (rare) | |
| TOL-TAZ | Class A β-lactamases (some of ESBLs, mainly K. pneumoniae, most of KPCs) |
| Class B MBLs | |
| Hyperproduction of AmpC (not in P. aeruginosa) | |
| Class D carbapenemases (OXA-48-like) | |
| MER-VAB | Class B MBLs |
| Class D carbapenemases (OXA-48-like) | |
| Porin alterations | |
| Hyperexpression of efflux pumps | |
| IMI-REL | Class B MBLs |
| Class D carbapenemases (OXA-48-like) | |
| Specific class A carbapenemases (e.g., GES) | |
| Hyperexpression of KPC | |
| Porin alterations |